Omicron Variants: The UKHSA said there is nothing to indicate increased levels of severity.(File)
The United Kingdom's coronavirus alert level has been reduced from four to three as COVID-19 cases continue to fall, even as two rare types of the Omicron variant sub-types have been reclassified as variants of concern.
Health authorities said on Friday that the current BA.2 driven Omicron wave is "subsiding" but it is expected that the number of cases will increase due to BA.4 and BA.5 sub-types, which the UK Health Security Agency (UKHSA) has elevated in classification to monitor their growth.
The agency said it will continue to analyse the rise as the full impact of the sub-types remains "uncertain".
"The reclassification of these variants as variants of concern reflects emerging evidence on the growth of BA.4 and BA.5 internationally and in the UK," said Dr Meera Chand, Director of Clinical and Emerging Infections at UKHSA.
"Whilst the impact of these variants is uncertain, the variant classification system aims to identify potential risk as early as possible. UKHSA is undertaking further detailed studies. Data and analysis will be released in due course through our regular surveillance reporting," she said.
Whilst Omicron BA.4 and BA.5 are in the early stages of growth in the UK, analysis of the available data suggests that they are likely to have a growth advantage over the currently dominant Omicron BA.2 variant.
There can be several reasons for the growth advantage, but in the case of BA.4 and BA.5 laboratory data suggests a degree of immune escape which is likely to contribute, experts note.
As of Thursday, the UKHSA said there had been 115 confirmed cases of BA.4 and 80 cases of BA.5 in the UK.
While it is expected that the variants may contribute to an increase in case numbers, there is nothing to indicate increased levels of severity.
"The current BA.2 driven Omicron wave is subsiding. Direct COVID-19 healthcare pressures continue to decrease in all nations and ONS community positivity estimates continue to decrease," the health chiefs for all parts of the United Kingdom said in a joint statement on Friday.
"Whilst it is reasonable to expect the number of cases to increase due to BA.4, BA.5 or BA2.12.1, it is unlikely in the immediate future to lead to significant direct COVID pressures. This will continue to be kept under review," they said.
The alert level was last raised in December last year as the Omicron variant spread rapidly.
The country's coronavirus infections are now believed to be at their lowest in five months, according to the latest Office for National Statistics community-based analysis.
(Except for the headline, this story has not been edited by NDTV staff and is published from a syndicated feed.)